Running Back: Damien Williams

Like the Oklahoma offense as a whole, Damien Williams had a quiet night.

The junior tallied a mere 41 yards on 16 carries along with 19 yards on five catches.

Despite his modest numbers, it's hard to rag on the junior tailback. The Sooner offense was forced to play catch-up for virtually the entire second half. This made the running game essentially a non-factor.

Backup running back Brennan Clay ended up leading the Sooners with 44 rushing yards on 10 carries. Collectively, OU generated 123 yards on the ground.

It would've been nice to see more production from the ground game, but that wasn't the biggest issue. The real mystery was the lack of passing output in the second half.

Defensive Ends: Chuka Ndulue and Geneo Grissom

Denny Medley-USA TODAY SportsChuka Ndulue (98) and Co. had their hands full against Johnny Manziel.

Grade: C-

The Oklahoma defense collectively failed to do its job Saturday night.

The defensive line was faced with the critical job of pressuring and containing Johnny Manziel. Based on his performance this season, Chuka Ndulue seemed capable of helping to do this.

But the sophomore end only mustered two tackles and failed to register a sack. More importantly, he couldn't keep the Heisman winner from getting outside and shredding the defense. Manziel ran for a record 229 yards and two touchdowns.

Geneo Grissom was similarly overmatched. In his first start of the season, the sophomore only accounted for one tackle.

One must temper the criticism, however. The D-line made an admirable effort. It also showed flashes of success in the first half at hemming in Manziel.

The lack of OU offense in the second half ultimately put an unbearable burden on the D-line, and Manziel and Co. took advantage of their opportunities.

Linebackers: Tom Wort and Corey Nelson

Tom Wort and Corey Nelson were basically invisible in Cowboys Stadium; they combined for three tackles and one tackle for loss.

Of course, high praise has to go to Manziel for his success. He is a uniquely gifted runner with keen instincts. But the linebacking unit provided little resistance.

When Manziel broke past the defensive line, it looked like a crater was substituting for the Sooner 'backers.

One of the reasons for the Sooners weak run defense this season is a lack of presence at linebacker. OU ranked 72nd in yards allowed entering the Cotton Bowl. Once again, Manziel exploited the suspect linebacking corps.

The Aggie pass game similarly profited from this lack of resistance. Ryan Swope and Co. complemented Manziel's rush attack.

Defense is a team effort, but the second level of the defense was woeful.

Nickelback Gabe Lynn; Cornerbacks Aaron Colvin and Demontre Hurst

USA TODAY SportsAaron Colvin led the Sooners with nine tackles against the Aggies.

Grade: B-

Statistically, Johnny Manziel's passing output was on par with his season averages.

He threw for 287 yards and two touchdowns against Oklahoma. In his 12 games prior to the Cotton Bowl, he averaged about 285 yards and two touchdowns per game. (This total doesn't account for the 20-yard reverse pass by Kenric McNeal).

Aaron Colvin accounted for a team-high nine tackles. Apart from that, nobody in this group stood out.

The pass defense could've been much worse, though. Manziel had plenty of time to throw, making pass coverage very difficult.

The Heisman winner's running potential made Colvin and Co.'s duties doubly challenging. Clearly, the defense in general was on its heels all night.